How to calculate book length

In an earlier post I discussed broad issues relating to word count and book length but didn’t actually explain how the length of a book is calculated. Let’s take a quick tour of copy fitting, casting off and related issues here.

Which side of the equation?

When we talk of copy fitting, generally we think of a publisher’s production editor or typesetter looking at fitting the delivered amount of text, tables, illustrations, etc. into a specific number of pages. (This is why, as recounted in my earlier post, so much fuss is made about authors delivering a ms according to what was specified in the author contract.)

However, in your case (especially if you are self-publishing your book or a bit worried about having hassles with your publisher), it may be smarter to look at the equation from the other side – to calculate the likely number of pages resulting from the setting of X thousand words, Y tables, Z illustrations, etc. This is also known as casting off.

More than word count

Obviously, a prime determinant of book size is the word count. No matter how much you adjust the other variables, if the ms is only 50,000 words in length instead of 95,000, then you have a problem if the book was announced as being 288 pages in length but the most it can be stretched to is 160 pages.

However, other variables do enter the equation, among them:

page size – academic books tend to follow a 9″ x 6″ (228 x 152 mm) format but the smaller traditional British Demy octavo format is also used a lot.

font/typeface – some fonts fill a lot more space than others but obviously here as elsewhere readability and what publishers want are also important considerations.

font size – this varies depending on font but usually it is between 10 and 12 points for body text, a bit smaller (sometimes much smaller) for notes.

line spacing (leading) – usually 1.2 times the font size with any deviation from this needing to be handled with care.

amount of normal text vs notes – as the font size for normal text is a bit bigger than for notes, the number of notes can have a significant effect on chapter/book extent.

number and size of tables and illustrations – calculate in terms of half and whole pages including captions. (The related issue of oversized tables and illustrations will be discussed in a later post, likewise problems with image resolution.)

word length – MS Word only counts the number of words not their length, nor does it care if your language is full of bombast and excess syllables. But, apart from being harder to read (the subject of forthcoming posts on readability and simple English), such ‘flab’ demands much more hyphenation of your text and even then the result will be looser text filling a far greater extent than the word count would imply.

chapter breaks – these can fall awkwardly (e.g. just before a new part that must start on a right-hand page) hence why it is more accurate to calculate the length of a book by its constituent parts than in the whole.

elements of the book – all of these constituent parts must be considered (e.g. space allocated for an index, something not delivered with the main ms).

sections – most books are printed on large sheets of paper folded and cut into 16-page sections. Part of the typesetter’s art is in ensuring that the number of blank pages at the end of the book is as low as possible.

Feel overwhelmed? If you do, then you are not alone. However, the above list is for typesetting nerds not ‘real’ people. For your purposes, many of the above elements can be safely ignored or incorporated into a simple procedure, as you shall see.

Making your estimate

If you have a page-layout program like Adobe InDesign, then it is a simple matter to calculate how many pages your manuscript will fill by creating a dummy book and then tweaking its layout parameters. Otherwise, you can make a pretty accurate calculation of the length of your book by following the steps below.

Create a map of your book, listing all of its elements in your first column. This map can be made on paper but it is relatively easy (and ultimately will save you a lot of time) to put it on a spreadsheet. (I will make available a sample Excel template for free download when I can sort out where to store such a file. Meantime, a screenshot of such a file is at the end of this post.)

On your map, define additional columns that later will hold the following values – in column 2: word count; 3: number of tables and illustrations; 4: calculated extent; 5: adjusted extent; 6: end page number

Determine the average number of words per page. Usually, this is about 400 for a standard academic book but only about 350 if the page size is Demy octavo. Changing the font, font size, leading, etc. will change this number a bit but, for your purposes, it is best to stick to these standard values.

Assign actual extents to those book elements where this is known (e.g. the first 4 pages of the prelims are standard and – depending on if you have a dedication, how detailed are your table of contents, and if you have lists of tables and illustrations – you can also safely guess the next few pages). For the index, you can probably only guess at this stage but here too you need a value. Enter these fixed values in columns 4 and 5.

Count the number of words for your preface, chapters, bibliography, etc., putting their values in column 2. Make sure that you include footnotes and endnotes (if using MS Word, by checking the appropriate box). Normally, it’s enough that you count these notes but obviously a lot of notes will skew your page calculation.

Count the number of tables and illustrations for each chapter (and other element in your book), putting their values in column 3. Although they may be much smaller, the assumption here is that each table or illustration fills an entire page. We’ll adjust for this in step 8.

Calculate the (unadjusted) extent of your preface, chapters, bibliography, etc. To do this, divide the word count by the words per page set in step 3, add a whole page for each table or illustration, then round up to a whole number of pages. Enter these calculated values in column 4.

Assess your calculated extents and put adjusted values in column 5. Reasons for doing this may be that some tables and illustrations are smaller than a whole page in size, there are a lot of endnotes (which will be set in a smaller font size), the chapter is followed by a part divider starting on a right-hand page, and the last page looks to be only a few lines long which could easily be saved in the typesetting.

Calculate a running total by adding the adjusted values, putting the end page number for each element in column 6 (i.e. the end page number for Chapter 4 is calculated by adding its adjusted page value to the end page number for Chapter 3). The final page number (effectively, the book’s grand total) will appear in the bottom row, that for your index.

Calculate the final extent (and number of blank pages at the end of the book). To do so, get the number of sections by dividing the grand total of pages by 16, then round up to a whole number of sections, multiplying these by 16.

Ten steps – it’s a simple as that.

Where now?

Is the likely extent of your book too long? Too short? In most cases, if the variation in length is only about a section (16 pages), then it probably won’t matter. Your publisher’s production editor or typesetter may swear a bit and try to tweak the book design so that all the material does exactly fit the announced book extent. But, if s/he fails, it is more than likely that your publisher won’t even blink at this slight variation.

However, if your book is likely to be significantly over or under its contracted/announced extent, now is the time to start sweating and thinking hard about how to retrieve the situation. Serious chocolates for your editor may be in order, but this may not be enough.

Extent calculation for the book, "Getting Published". (Note that pagination restarts after prelims.)

Thank you for this information. As a beginning academic, I need to hear specifics. Great info on book length, word count, etc., essential for book proposals. Hope to get mine out by the end of the summer.